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HomeMy WebLinkAboutCity Council Committees - Public Works/Planning - 04/02/1991 PUBLIC WORKS COMMITTEE APRIL 2, 1991 PRESENT: Jim White Tony McCarthy Leona Orr Jack Spencer Steve Dowell Mr. and Mrs. Rust Don Wickstrom Steven R. Wheatley Carol Morris Tony Segale Tom Brubaker Charlie Kiefer Gary Gill William Joy Ed White Gary Phillips Tim Heydon Siggi Finnsson Karen Siegel Tunnel Technology Presentation Wickstrom introduced Gary Phillips of Wilsey and Ham, Pacific and Siggi Finnsson of the Robbins Company who will review the concepts and costs associated with construction of a tunnel. Gary Phillips stated that a tunnel alternative for the two proposed alignments of the 272nd/277th corridor. Both were proposed to have 800 foot horizontal curves connecting on both sides to the roadway sections. The east wall is a relatively undisturbed forested area that has steep slopes and ravines generally running from elevation 50 up to the plateau which is elevation 400. The site investigation revealed the soils are silty sand, some gravels, cobbles and scattered boulders. The tunnel would be approximately 4, 000 feet in length, requiring two twin bores, one for the downhill direction and one for the uphill direction. The grade for the tunnels would range from 6-1/1 to 8%. It would be a 40-foot diameter bore. The downhill bore would be two lanes with pedestrian access. The uphill portion would be a three lane facility where you have a climbing lane inside the tunnel. The tunnel technique proposed is an "Earth Pressure Balance", ETB system with a slurry shield. The tunneling alone is approximately $50 million. That does not include any facilities that would be required for inside the tunnel, roadway, ventilation, lighting, etc. In order to come up with a representative cost for the whole tunnel inside facilities had to be considered. These included ventilation, fire protection, drainage, lighting, and tunnel lining. Looking at the tunnel environment itself, the types of materials used inside the tunnel because of the exhaust and different types of chemical reactions, requires more extensive material than a typical roadway or bridge structure. The estimate was roughly $80 million for the two 4, 000-foot tunnel sections. Public Works Committee April 2, 1991 Page 2 Most of the costs are associated with the tunneling itself. Siggi Finnsson of Robbins Company stated that tunneling machines can be split into two groups. one being hard rock and the other being soft ground. The geology of this hill consists of soft ground. Soft ground machines can be any of three different kinds, excavator shields, pressure valve shields, or slurry shields. Photos of various types of machines were displayed and discussed. He stated this type of tunnel would be lined by pre-cast reinforced concrete segments taking place as the machine advances through the ground. There would be nine segments to a ring each weighing about 10, 000 pounds. The specifications of a machine that would construct this type of tunnel would be approximately 40 feet in diameter, advance rate of approximately 4 feet per hour, weight of the machine would be about 4 million pounds. Jim White asked about the comparison of cost - tunneling versus standard construction. Wickstrom responded it would be approximately $20 million to construct the 2 mile project using conventional construction methods versus about $90 million to construct including the tunnel. White continued that it appears even with a tunnel there is quite an operation above ground and would be disturbing the environment in any case. Siggi Finnsson clarified that the disturbance would occur at the portals. On top of the actual tunnel there would not be any construction unless you wanted to construct ventilation shafts. It was explained that a tunnel of this length would require ventilation shafts. Structures at each end of the portal would require clear ceiling heights of 25 feet. You would need three large fans in order to provide ventilation in each of the structures. White asked about the cost to maintain a tunnel versus an open roadway. Phillips continued that it should be lined with a ceramic tile to reduce maintenance. Wickstrom added that you would still have the cost of maintaining the road structure in addition to the cost of the tunnel maintenance. There would still be the drainage facilities to maintain as well. There was a question as to what happens to the dirt. Wickstrom stated that was a factor that still had to be determined. We do know that because of the quality of the soils it could only be used summer fill. White asked when the proposed alignments on the corridor would be brought before Council. Wickstrom explained when the EIS is completed then it will be brought before Council for selection of the preferred route and adoption of the EIS. It could be brought before Council before that time in the appeal process. Public Works Committee April 2, 1991 Page 3 Recycling Resolution Karen Siegel explained that in recognition of Earth Day 1991, the Earth Day Committee, which consists of volunteers from several City departments, decided to rejuvenate the City's in-house recycling program. While participation is voluntary on the part of the employees, the Committee felt that adoption of a resolution establishing a policy of in-house recycling would establish the identity of the program and emphasize its importance. It will make a statement to the employees that the City is dedicated to the program and will also serve to show the community that the City is dedicated to recycling efforts. Orr commented that this was a great idea. The Committee unanimously recommended approval. Parkside Division #2 Walkway Wickstrom stated this item is mostly an informational one. We have had our legal staff review the concerns brought up by Mr. Venables. They have determined there is no merit to Mr. Venables legal arguments. Surplus Equipment Wickstrom presented a list of equipment to be surplused. The Committee unanimously recommended approval to surplus and sell the equipment. Status of Garbage Disposal Issue Wickstrom stated he wanted to bring the Committee up to date on the status of the settlement of the issue. The haulers have settled on their service areas and effective April 1 there could be a change. inhaulers for the commercial customers. Water System Improvements - Transfer of Funds Wickstrom stated that after opening bids on this prd -1a it appears the budget is about $110, 000 short. A large portion - , the overrun is due to, the need to hire a consultant to provide construction management. Because we have not been able to �fil1 budgeted positions this year, the vacancy of the Construoti6n Engineer position and the work load of the existing staff, we ,are having to manage this project through a consultant. Wickstrom Stated he was recommending the transfer of $110, 000 from the unencumbered water fund. IBC has approved this transfer and we will betaking it to Operations because of the budget change. The Committee unanimously recommended approval of the transfer of the funds. Public Works Committee April 2 , 1991 Page 4 Puget Sound Regional Council Interlocal Agreement Wickstrom explained that an interlocal agreement has been developed which would create a Puget Sound Regional Council instead of the PSCOG. This Council would primarily coordinate the road projects and disburse federal funds. Passage requires approval' of cities representing 60% of the population. White commented there is concern at the Suburban Cities level about issues being brought before the Council from the County and the PSCOG at the last minute. There needs to be time to thoroughly review these issues. The Committee unanimously recommended approval. Proposed LID 218th Street Wickstrom distributed a memorandum prepared by the legal department outlining the legal options the Rusts would have for assessment deferral. Tom Brubaker reviewed the contents of the memorandum. The Rusts can only be assessed to the degree their property is specially benefitted. Therefore, if there is a wetland area designation or some designation on their property that would make any portion undevelopable, their assessment would have to be proportionately reduced. There is a statutory exemption from special assessments on LID for farm and agricultural land. This is probably one of the most difficult classifications for the Rusts to achieve as they would have had to have a gross income from the property of at least $1, 000 for three of the past five years. There is a statutory framework for people over the age of 61 if they can show the necessary need to defer payment and have the state pay the installments on the assessments. Brubaker continued that the Rusts may be eligible for this but the state charges an 8% interest charge on their payments. So, the Rusts would end up paying the installment on the assessment, the interest on the bond and then 8% interest on top of that. There is a statutory enactment that legitimizes latecomer agreements on LID's. If an adjacent property owner wishes to pay the assessment up front, we can, in the enacting ordinance, include terms for the repayment of the assessment upon the occurrence of certain conditions such as sale of property, property development, etc. There could also be private agreements between the Rusts and others, perhaps a life estate, creative financing. Brubaker stated he has also been in contact with the Rust's attorney. Mr. Rust had a question about the wetland designation. Wickstrom responded that any development that would occur would have to show by additional analysis that it is a wetland or that only a portion �1 " Public Works Committee April 2, 1991 Page 5 thereof is a wetland. That is primarily an issue the SEPA official would review at the time a development permit is sought. Mr. Rust stated that they would have to go through the ritual of proving their property is not a wetland so they can develop. Wickstrom stated that in today's market either a developer or lending institution would require both a wetland analysis and hazardous substance analysis on any property before consummation of a sale. Leona Orr questioned for future LIDs if there is any procedure we can set in place that would prevent property owners from being displaced, by the burden of LID assessments. It was determined that Council does have the authority to vote against the formation of an LID. Brubaker informed the Committee there are attempts underway both by the Rust's attorney and by the City to find a solution to the problem. Other Charlie Kiefer asked about the status of the draft EIS for the 272nd/277th Corridor. Wickstrom stated that the City's draft EIS would be available approximately July - September. The County is doing their own traffic study to establish the priority of the corridor projects.